Procedures for the purification of large quantities of plasma membranes (PM) from boar sperm have been developed and the outer acrosomal membrane (OAM) from the same species has been partially purified. This proposal expands this work to provide a reference two-dimensional polypeptide map of the boar spermatozoan surface which will describe (a) the distribution of polypeptides in different regions of the sperm surface, (b) those polypeptides that are sperm-membrane specific, (c) the orientation of polypeptides within the membrane, and (d) those polypeptides that originate in the seminal plasma and epididymis. Chromatographic methods will be developed for the fractionation of PM glycoproteins in quantities sufficient for chemical and structural analyses. The OAM will be purified and its lipid, carbohydrate, polypeptide, and antigenic properties determined. Chromatographic and electrophoretic procedures will be supplemented by immunocytochemical techniques using fluorescence and electron microscopy for the regional location of membrane proteins.